<template>
    <div id="product-detail">
      <nav class="top-navbar" :class="{ fixed: isSticky }">
      <div class="back">
        <button>&lt;</button>
      </div>
      <div class="nav-right">
        <a href="#" class="nav-link">首页</a>
        <a href="#" class="nav-link">个人中心</a>
        <a href="#" class="nav-link">购物车</a>
        <a href="#" class="nav-link">收藏夹</a>
        <a href="#" class="nav-link">帮助中心</a>
        <button class="sign-in-button" @click="showLoginDialog = true">Sign in</button>
        <button class="register-button" @click="showRegisterDialog = true">Register</button>
        <button v-if="isLoggedIn" class="sign-out-button" @click="logout">Sign out</button>
      </div>
    </nav>
      <div class="product-detail-container">
        <h2>{{ product.name }}</h2>
        <img :src="product.image" alt="product" class="product-detail-image" />
        <p class="product-description">{{ product.description }}</p>
        <span class="product-price">¥{{ product.price }}</span>
        <button class="add-to-cart-button">加入购物车</button>
      </div>
    </div>
  </template>
  
  <script setup>
  import { ref, onMounted, onBeforeUnmount } from "vue";
  import { useRoute, useRouter } from "vue-router";
  
  const route = useRoute();
  const router = useRouter();
  
  const product = ref({
    id: null,
    name: "",
    price: 0,
    image: "",
    description: "",
  });
  
  const isSticky = ref(false);
  
  const mockProducts = {
    1: {
      name: "商品1",
      price: 100,
      image: "https://via.placeholder.com/300",
      description: "这是商品1的详细描述。",
    },
    2: {
      name: "商品2",
      price: 200,
      image: "https://via.placeholder.com/300",
      description: "这是商品2的详细描述。",
    },
    3: {
      name: "商品3",
      price: 150,
      image: "https://via.placeholder.com/300",
      description: "这是商品3的详细描述。",
    },
  };
  
  const handleScroll = () => {
    isSticky.value = window.pageYOffset > 0;
  };
  
  const goBack = () => {
    router.push({ name: "ProductHome" });
  };
  
  onMounted(() => {
    const productId = parseInt(route.params.id, 10);
    product.value = mockProducts[productId] || { name: "未知商品", price: 0, image: "", description: "" };
    window.addEventListener("scroll", handleScroll);
  });
  
  onBeforeUnmount(() => {
    window.removeEventListener("scroll", handleScroll);
  });
  </script>
  
  <style scoped>
  .product-detail-container {
    padding: 20px;
    text-align: center;
  }
  .product-detail-image {
    width: 300px;
    height: auto;
    margin: 20px 0;
  }
  .product-description {
    margin: 20px 0;
    font-size: 16px;
    color: #666;
  }
  .add-to-cart-button {
    padding: 10px 20px;
    background-color: #333;
    color: white;
    border: none;
    cursor: pointer;
  }
  * {
  margin: 0 auto;
  padding: 0;
}
#app {
  width: 100vw;
  height: auto;
  margin: 0;
  padding-top: 0;
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
}
.top-navbar {
  display: flex;
  justify-content: space-between;
  gap: 20vh;
  background-color: #f4f4f4;
  padding: 10px;
  position: relative;
  z-index: 100px;
  transition: all 0.3s ease;
}
.back {
  display: flex;
  justify-content: start;
}
.nav-right {
  display: flex;
  align-content: flex-end;
}
.nav-link:hover {
  color: white;
  background-color: #333;
  border-radius: 20%;
}
.fixed {
  position: sticky;
  top: 0;
  width: 100%;
  background-color: #f4f4f4;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}
.nav-link {
  margin-right: 20px;
  text-decoration: none;
  color: #333;
}
.sign-in-button,
.register-button,
.sign-out-button {
  background-color: #333;
  color: white;
  border: none;
  padding: 5px 10px;
  cursor: pointer;
}
  </style>